


The case of the polymurders

by SilverBells



Category: Harry Potter - J. K. Rowling, Sherlock (TV), Sherlock Holmes & Related Fandoms
Genre: Complete, Crossover, Drabble, Gen, John is magic, Polyjuice Potion, Tumblr Prompt, harry potter & sherlock holmes, what could possibly go wrong
Language: English
Status: Completed
Published: 2013-07-31
Updated: 2013-07-31
Packaged: 2017-12-21 23:51:36
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 766
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/906420
Author URL: https://archiveofourown.org/users/SilverBells/pseuds/SilverBells
Summary: <blockquote class="userstuff">
              <p>Sherlock encounters a case that requires there to be two of him. Thankfully, John hasn't broken with all of his magical heritage.</p>
            </blockquote>





	The case of the polymurders

Moral of the story; do never tell Sherlock Holmes something is impossible simply because he cannot be in two places at once. 

Also, walking around with stelts for legs is hazardous for one’s health and John wonders how Sherlock manages this _all the time._

“This is,” John begins, as he stares at himself in the mirror, “By far, the most idiotic thing you’ve ever had me do, Sherlock, and that’s saying something.”  
The lines of his face have rearranged themselves into the sharp angles of Sherlock’s and his own eyes, already light, have paled even further, but his hair, in contrast, has darkened. It’s longer and curls over his forehead. It’s all so familiar and so incredibly strange to see when he looks at the mirror. He can’t help but touch a skinny, elongated finger to its surface and he sighs. 

John turns around to look at his flatmate. The polyjuice potion has worked perfectly, because there’s no difference between the man in front of him and the image in the mirror. He thanks himself again for keeping in contact with Remus all these years, he’s not sure if he could have pulled this off on his own. 

Sherlock doesn’t respond, but simply hands him one of his suits to put on; it’s nearly identical to the one he’s wearing. He seems unpertubed by the sight of his own almost-naked body, which is logical, John thinks, but he has to admit a certain fascination. Not by the naked stretch of pale skin, god knows he’s seen that before, but by the fact that it’s Sherlock’s body, wearing _his_ red boxer-briefs. 

John is glad he’d taken the precaution of taking off the rest of his clothing before drinking the potion, which had turned a deep, velvety dark red after the addition of one of Sherlock’s hairs, because they certainly would have been ruined, seeing as he’s gained about a foot in length. The new clothes fit perfectly, of course, though they’re a little stiff, and he’s grateful when Sherlock helps him slide on the jacket. 

He kind of wants to start bickering about the legality of the whole ordeal — if anyone were to see them together! — but they’ve had that discussion and he knows he’s quite unable to say no to Sherlock. He might as well resign himself to the fact that he’ll be running around Londen, pretending to be the consulting detective for the remaining part of the afternoon, trying to solve what John has already nicknamed the case of the polymurders. He’s not sure how he’s going to tell this story without revealing they used magic to solve the case of identical murders taking place at exactly the same time, but he’ll figure out a way to do it. It’s a very interesting story, after all. 

He wipes his hand over his mouth and feels a few crumbs left there after lunch. He wonders if it would have tasted different if he’d eaten it with Sherlock’s mouth. 

“I’m still not okay with you using my magic to solve cases, Sherlock,” he says, though there’s no attack in this words, “But are you sure this’ll work? I still sound like myself.” 

Sherlock smoothes his hands over John’s shoulders — well, his own shoulders, technically speaking — and then straightens his own jacket. John pulls at the sleeves of his self-counsciously, as Sherlock observes him. 

“Jes, John, of course it will work,” he replies, and the way he looks at his friend reassures John somehow. It’s the same way he always looks at him, instead of the way he usually looks when he gets a glance at himself in the mirror, “Just follow the plan, you’ll be fine.” 

There’s a calculating, but approving look in Sherlock’s eyes, as his face smoothes into a soft smile. Well — as much of a smile as Sherlock can muster. “I know no-one better suited for the task of being me.” 

John just stares at him for a bit and then nodds, “Yeah, okay, allright.” He wobbles back and forth on his heels a bit and it feels strange to do that in this body, “Thank you.” It’s one of Sherlock’s rare, not-compliments, but John takes it anway. 

Sherlock tilts his head — John puts it on his list of things to do when he’s pretending to be Sherlock — and then turns around, stalking out of the appartment at his usual brisk pace. 

“Oh, and John?” he says, as he turns around on the doorstep, startling John, who’d been just about to follow in his footsteps, quite literally, “Wipe those biscuit crumbs off my jacket.”

**Author's Note:**

> I saw this http://consulting-angel-of-the-lord.tumblr.com/post/56961728958/david-tennants-companion on tumblr and couldn't resist :)


End file.
